Batteries run dry

[Isabella42]

I have a question about why my batteries are constantly running dry. My GB42 is 1500 miles away from my home but I travel to it frequently at a secure marina where she is on shore power. It seems that within a month of my filling up the batteries with distilled water, they are completely dry. Can anyone tell me why this is happening and what I can do to prevent this from occurring?
Thanks.

 

[DavidM]

The problem is probably the battery charger. Old ones before the days of three step chargers, charge with a single voltage. Sometimes it is too high and boils (well disassociates) the electrolyte.

What make/model of charger do you have?

Or I guess you could have a case leak.

BTW batteries that have been dry for a few days are probably toast.

David

 

[kthoennes]

During that extensive recent discussion about whether distilled water was really necessary in batteries, I checked mine. One was bone dry and one was badly depleted (like one third down) but not dry. I pulled and filled them both and put them on trickle chargers. One came back okay (13.1) but the bone-dry battery was toast and never came back, just as David says. My charger was original to the boat, 1995/6, a "dumb" charger so just for general purposes I upgraded to a smart charger. Bought it used for a really good price, a Charles 60 amp/variable battery type from just before Charles stopped making marine chargers, but it's only a few years old and I hope will do a better, more careful job on the batteries and won't run them dry quickly.

 

[SteveK]

I came back to the boat after about a month away. Checked electrolyte and all read full charge average 12.80. Proceeded to top up with distilled and about 50% needed a little.

Point is I have a 3 stage charger and it sits at float most of the time.
Your batteries are overcharged. When you do get new batteries, also get a 3 stage charger.